: People with severe speech impairments who use utterance-based augmentative and alternative communication (AAC) systems are forced to make less than optimal choices when delivering messages, resulting in communication that is flawed with respect to either the speed of message delivery or the appropriateness of message content. These choices involve a violation of one conversational rule to satisfy another. A working model of conversational trade-off choices in AAC, developed and initially tested during the previous grant period, identifies the relative effects of specific trade-off choices involving selected rules on attitudes of public service providers toward adult AAC system users and their communication in a bookstore setting. A hierarchy of trade-off choices involving a particular degree of each rule violation emerged in this setting. The specific aim of the proposed research is to test the generalization of the obtained hierarchy across multiple degrees of violation within a given rule violation type and across multiple public settings. This will be accomplished first by an experiment seeking to determine whether altering the degrees of a given type of violation (i.e., redundancy, speed of message delivery, excessive information, inadequate information, and relevance) will change its position along the hierarchy. Next, a series of experiments will determine the extent to which the hierarchy generalizes to AAC interactions in five different public settings, each differing with respect to particular features. Participant contingent responses to the violations in each experiment will be obtained as an initial step in understanding how these violations are managed. Regardless of the variables to be evaluated, it is predicted that the same hierarchy of trade-off choices will be evident, such that some will have a more favorable effect than others on public attitudes toward AAC users and their communication. The findings will guide future systems development to support the strategies that will be most effective for the user and partner in dealing with rule violations, thereby significantly contributing to the user's success in achieving independence, acceptance, and inclusion in society. The findings will also contribute to advances in pragmatic theory. The long-term goal is to formulate a theory of conversational trade-off choices and repair in AAC to better understand the effects of deviant communicative behavior in situations where expectations of conventional behavior apply so that appropriate technologies for utterance-based systems can be developed.